Such connection strips are already known per se. They have multiple connection points for the conductors of the cable(s) on one of their faces, namely the "rear" face under conditions of use, an to the same number of connection points for the pairs of conductors in different jumpers on their other, or "front" face.
The connections made on the rear face are considered to be fixed and final. Except under exceptional circumstances, no action normally needs to be taken on this rear face. In contrast, the front face is where all the action takes place for installing or replacing jumpers or the changing connections.
One such connection strip is described in the patent U.S. Pat. No. 4,652,070, in particular. That strip is in the form of a block of insulating material in which a plurality of connection elements are mounted. The connection elements define connection points in a plurality of rows both on the front face and on the rear face of the strip.
Before any action is taken on the front face, the connection elements terminate in chimneys defined in longitudinal ribs projecting from said face. Each rib corresponds to a row of connection points. The ribs are separated from one another by valleys to allow jumpers to pass between them.
The individual connection elements mounted in the insulating block are either in the form of single pieces, or else in the form of pairs of pieces which are connected together. In the front face, they have respective insulation-displacement connector forks in the various chimneys defined on the front face, and at their opposite ends in the rear face of the block they have connectors that may be of the same type or of a different type. Each insulation-displacement connector receives a corresponding insulated conductor which is directly connected thereto without prior stripping, merely by being displaced within the connector. Slots provided in opposite sides of each chimney on the line between the branches of each fork enable the conductors to move within the insulation displacement connectors.
According to that document, pushers are also associated with the connection strip for simultaneously connecting the two conductors of each jumper in two adjacent insulation-displacement connectors in the same row.
These pushers are made of insulating material. Each of them has two legs that fit the chimneys and that are connected together by a bridge at one end. Each pusher receives the two conductors of a jumper inserted through respective ones of its legs close to the bridge joining them. These two conductors are connected simultaneously to the two insulation-displacement connectors by pushing home the two legs of the pusher into two chimneys. The bridge joining the two legs is held in the hand during insertion and also serves in particular as an end stop for the pusher in the two chimneys closed thereby. In addition, it serves for removing a pusher that has been installed.
Although such a strip is satisfactory overall, it nevertheless suffers from several practical problems due essentially to the environmental conditions in which it is used and to the density of the connections that it achieves. This applies in particular in a high humidity environment since that may give rise to damaging condensation on the connections. It also applies to the actions involved when installing new jumpers or when changing existing jumper connections because of the large number of jumpers passing between each row of insulation displacement connectors.
An object of the present invention is to avoid these problems, in particular by increasing the creepage distances between the insulation displacement connectors within a small space, and also by facilitating conductor handling in the event of jumpers being replaced or changed over.